Background: Klippel-Trenaunay syndrome is a non-heritable venous malformation with bone and soft tissue hypertrophy and cutaneous nevi.
Case characteristics: Neonate with Klippel Trenaunay syndrome born to a mother with past history of Gestational trophoblastic neoplasm.
Observation: Antenatally, a fetal vascular malformation was identified ultrasonologically at 29 weeks gestation. Acute myeloid leukemia was diagnosed in mother at 33 weeks gestation.
Message: A rare association of Klippel Trenaunay syndrome and gestational trophoblastic neoplasm with the possible role of either hyperglycosylated Human Chorionic Gonadotropin or chemotherapy as a link is highlighted.